How to Make a image repeat in cycles
All you need to do to get an image to repeat in a Cycles material is add a Vector > Mapping node between the Texture Coordinates and Image Texture.  Set the Mapping node to Texture at the top and set any of the Scale: values to less than one to make the image repeat along a certain (or multiple) axis(axes).



The other option, without adding any other nodes, is to simply scale up the UVmap in the UV/Image Editor. A UV map larger then the image will make the image repeat.